feat(engine): add order-insensitive container node matching

internal/actions/chawathe.go

@@ -217,6 +217,10 @@ func (s *chawatheState) findPos(x *treesitter.ASTNode) int {
 }
 
 func (s *chawatheState) alignChildren(w *cnode, x *treesitter.ASTNode) {
+	if w == nil || x == nil {
+		return
+	}
+
 	for _, c := range w.children {
 		delete(s.srcInOrder, c)
 	}
@@ -242,6 +246,16 @@ func (s *chawatheState) alignChildren(w *cnode, x *treesitter.ASTNode) {
 		}
 	}
 
+	if x.IsUnordered || (w.orig != nil && w.orig.IsUnordered) {
+		for _, b := range s2 {
+			if a, ok := s.cpyDstToSrc[b]; ok {
+				s.srcInOrder[a] = true
+				s.dstInOrder[b] = true
+			}
+		}
+		return
+	}
+
 	lcsPairs := s.lcs(s1, s2)
 
 	lcsSet := make(map[*cnode]bool)

internal/actions/chawathe_test.go

@@ -0,0 +1,43 @@
+package actions
+
+import (
+	"testing"
+
+	"github.com/HarshK97/diffmantic/internal/engine"
+	"github.com/HarshK97/diffmantic/internal/treesitter"
+)
+
+func TestUnorderedNodeMatching(t *testing.T) {
+	// Create two container nodes with reordered child nodes
+	childA1 := &treesitter.ASTNode{Type: "pair", Label: "a"}
+	childB1 := &treesitter.ASTNode{Type: "pair", Label: "b"}
+	src := &treesitter.ASTNode{
+		Type:        "object",
+		IsUnordered: true,
+		Children:    []*treesitter.ASTNode{childA1, childB1},
+	}
+	childA1.Parent = src
+	childB1.Parent = src
+
+	childB2 := &treesitter.ASTNode{Type: "pair", Label: "b"}
+	childA2 := &treesitter.ASTNode{Type: "pair", Label: "a"}
+	dst := &treesitter.ASTNode{
+		Type:        "object",
+		IsUnordered: true,
+		Children:    []*treesitter.ASTNode{childB2, childA2},
+	}
+	childB2.Parent = dst
+	childA2.Parent = dst
+
+	ms := engine.NewMapping()
+	ms.Add(src, dst)
+	ms.Add(childA1, childA2)
+	ms.Add(childB1, childB2)
+
+	script := GenerateEditScript(src, dst, ms)
+	for _, action := range script.Actions() {
+		if action.Type == Move {
+			t.Errorf("expected 0 Move actions for unordered container, got Move action on node %s", action.Node.Label)
+		}
+	}
+}

internal/engine/bottom-up.go

@@ -103,8 +103,10 @@ func candidate(
 	bestDice := -1.0
 	bestLabelScore := -1
 	var bestSamePositional bool
+	var bestKeyMatched bool
 
 	t1Labels := t1.LeafLabels()
+	t1Key := getKeyLabel(t1)
 
 	for _, c := range candidates {
 		if m.HasDst(c) {
@@ -138,8 +140,14 @@ func candidate(
 		diff := sim - bestSim
 		isBetter := false
 		ls := labelOverlap(t1Labels, c)
+		cKey := getKeyLabel(c)
+		keyMatched := t1Key != "" && cKey != "" && t1Key == cKey
 
-		if math.Abs(diff) > 0.05 {
+		if t1Key != "" && keyMatched != bestKeyMatched && t1.IsUnordered {
+			if keyMatched {
+				isBetter = true
+			}
+		} else if math.Abs(diff) > 0.05 {
 			if sim > bestSim {
 				isBetter = true
 			}
@@ -169,11 +177,28 @@ func candidate(
 			best = c
 			bestLabelScore = ls
 			bestSamePositional = samePositional
+			bestKeyMatched = keyMatched
 		}
 	}
 	return best
 }
 
+func getKeyLabel(n *treesitter.ASTNode) string {
+	if n == nil || len(n.Children) == 0 {
+		return ""
+	}
+	k := n.Children[0]
+	if k.Label != "" {
+		return k.Label
+	}
+	for _, desc := range k.Descendants() {
+		if desc.Label != "" {
+			return desc.Label
+		}
+	}
+	return ""
+}
+
 // labelOverlap returns the number of shared leaf labels in t2's subtree.
 func labelOverlap(t1Labels map[string]int, t2 *treesitter.ASTNode) int {
 	count := 0

internal/treesitter/ast.go

@@ -22,6 +22,7 @@ type ASTNode struct {
 	HasError        bool   // True if parse tree contained any ERROR nodes
 	ParseErrorCount int    // Total count of ERROR nodes in parse tree
 	IsKeyword       bool   // True if node is a keyword token
+	IsUnordered     bool   // True if children of this container node are order-insensitive
 
 	// Hash is the combined hash of node type, label, and children.
 	Hash uint64
@@ -186,6 +187,9 @@ func buildASTWithRules(n *gotreesitter.Node, src []byte, lang *gotreesitter.Lang
 		if slices.Contains(rules.Keywords, nodeType) || (label != "" && slices.Contains(rules.Keywords, label)) {
 			node.IsKeyword = true
 		}
+		if slices.Contains(rules.Unordered, node.Type) {
+			node.IsUnordered = true
+		}
 	}
 
 	for i := 0; i < n.ChildCount(); i++ {

internal/treesitter/go/rules.yml

@@ -124,4 +124,8 @@ declarations:
   - const_declaration
   - var_declaration
 
+unordered:
+  - interface_type
+
+
 

internal/treesitter/java/rules.yml

@@ -187,4 +187,8 @@ declarations:
   - local_variable_declaration
   - field_declaration
 
+unordered:
+  - annotation
+
+
 

internal/treesitter/javascript/rules.yml

@@ -173,4 +173,10 @@ declarations:
   - lexical_declaration
   - field_definition
 
+unordered:
+  - object
+  - object_pattern
+
+
+
 

internal/treesitter/php/rules.yml

@@ -171,4 +171,8 @@ declarations:
   - property_declaration
   - const_declaration
 
+unordered:
+  - array_creation_expression
+  - attribute_group
+  - attribute_list
 

internal/treesitter/python/rules.yml

@@ -155,4 +155,9 @@ declarations:
   - function_definition
   - class_definition
 
+unordered:
+  - dictionary
+  - set
+
+
 

internal/treesitter/ruby/rules.yml

@@ -155,3 +155,9 @@ declarations:
   - class
   - module
 
+unordered:
+  - hash
+  - hash_pattern
+
+
+

internal/treesitter/rules.go

@@ -16,6 +16,7 @@ type Rules struct {
 	Scaffolding  []string          `yaml:"scaffolding"`
 	Keywords     []string          `yaml:"keywords"`
 	Declarations []string          `yaml:"declarations"`
+	Unordered    []string          `yaml:"unordered"`
 }
 
 //go:embed */rules.yml

internal/treesitter/rules_test.go

@@ -182,3 +182,15 @@ func TestRulesAliased(t *testing.T) {
 		})
 	}
 }
+
+func TestRulesUnordered(t *testing.T) {
+	r := &Rules{
+		Unordered: []string{"object", "start_tag"},
+	}
+	if len(r.Unordered) != 2 {
+		t.Fatalf("expected 2 unordered entries, got %d", len(r.Unordered))
+	}
+	if r.Unordered[0] != "object" || r.Unordered[1] != "start_tag" {
+		t.Errorf("unexpected unordered entries: %v", r.Unordered)
+	}
+}

internal/treesitter/rust/rules.yml

@@ -151,4 +151,8 @@ declarations:
   - const_item
   - static_item
 
+unordered:
+  - use_declaration
+
+
 

internal/treesitter/tsx/rules.yml

@@ -189,4 +189,14 @@ declarations:
   - variable_declaration
   - lexical_declaration
 
+unordered:
+  - object
+  - interface_body
+  - object_type
+  - jsx_opening_element
+  - jsx_self_closing_element
+  - object_pattern
+
+
+
 

internal/treesitter/typescript/rules.yml

@@ -175,4 +175,12 @@ declarations:
   - variable_declaration
   - lexical_declaration
 
+unordered:
+  - object
+  - interface_body
+  - object_type
+  - object_pattern
+
+
+